The development and extensive application of electronic elements have become one of the important symbols for the development of electronic industry of a nation. Presently, various electronic elements, including passive, electromechanical, acoustic and composite elements, are in a trend to complication, precision and miniaturization. On this account, carrier-tape used for packing, transportation and acquisition of electronic elements is of vital importance to the protection of electronic elements. Existing carrier-tape can be divided into plastic carrier-tape and base paper carrier-tape by material. As it is difficult to ensure the dimensional precision of plastic carrier-tape, and to eliminate the chamfer in case of punching; moreover, plastic material is unavailable for buffer, which may incur mechanical damages to electronic elements, plastic carrier-tape has been gradually replaced by base paper carrier-tape featuring in high resilience, easy production and low cost. However, strength of the base paper is inferior to that of the plastics, which may produce dust to the extent of affecting the performance of electronic elements and incurring blockage to relevant components. Moreover, chemical composition of the base paper may also affect the quality of electronic elements, etc.
In view of the fact that chemical composition of the base paper may affect the quality of electronic elements, Patent CN1579756A renders a carrier-tape material that can prevent corrosion to installations on the surface thereof. Such material is in multilayer papermaking structure composed of various pulpwood, which aims to control the residual sulfate ion content below 500 ppm through adjustment of surface pH value to 6.0˜8.0. Meanwhile, 1.0˜8.0 and 0.1˜1.0 parts of paper strength agent and tackifier respectively are added to 100 parts of multilayer pulpwood by weight, aiming to adjust the moisture of wet paper to be extruded to 75˜80%.
Patent CN1593910A discloses a carrier-tape material that can link up the covered tape via thermal sealing to prevent unexpected peeling without causing damages to the paper when the covered tape is stripped. According to the technical solution, liquid containing 90:10˜50:50 water-soluble polymer and styrene acrylic resin (melting point: 80˜120° C.) is coated on the surface and/or backface of the carrier-tape made of material containing pulp fiber.
Patent CN1629401A renders a carrier-tape base paper featuring limited thickness variation and zero deviation to operation efficiency; its technical solution is stated as follows: The base paper is to be made into multilayer acid paper with rosin filler added to the intermediate layer; alternatively, it can also be made into multilayer neutral copy paper with alkyl ketene dimer filler added to the intermediate layer; the mass fraction of the filler corresponding to 100 mass fractions of fully dried pulp is 0.1˜50.75.
Aforesaid patents are expected to change the mass of the base paper by changing material composition, which are unlikely to cater to such performances simultaneously as smoothness and high strength of the surface, perfect flexibility and limited physical damages of the intermediate part, and high resilience of the backface; these preferences are important to the normal operation of the carrier-tape and the quality of electronic elements.